Hello!
It sounds like you've been putting in a lot of effort despite your busy schedule, which is commendable. Based on your practice test scores, it seems like you're fluctuating a bit, which is not uncommon. Here are a few points to consider:
Assess your progress: Look at the areas where you struggled in your practice tests. Are there specific sections (Quant, Verbal, Integrated Reasoning, or Analytical Writing) where you consistently score lower? Focusing on those areas could help improve your overall score.
Quality over quantity: With your limited study time, make sure you're using effective study materials and strategies. Consider focusing on high-yield topics and practicing with official GMAT questions.
Consider rescheduling: If you feel that you need more time to improve your scores and build confidence, it might be wise to reschedule. Aiming for a score of 645 and above is a great goal, but it's important to feel prepared on test day.
Practice under test conditions: As you continue to study, try to simulate test conditions as closely as possible during your practice tests. This can help you manage time and stress better on the actual test day.
Stay positive and manage stress: Balancing a full-time job and GMAT prep can be challenging. Make sure to take care of your mental health and find ways to manage stress, whether through exercise, meditation, or other activities you enjoy.
Ultimately, trust your instincts about whether to reschedule. If you believe that a little more preparation will make a significant difference, it’s worth considering. Good luck!